Parallel-NetCDF is a library providing high-performance I/O while still
maintaining file-format compatibility with Unidata's NetCDF. NetCDF gives
scientific programmers a space-efficient and portable means for storing data.
However, it does so in a serial manner, making it difficult to achieve high I/O
performance. By making some small changes to the API specified by NetCDF, we can
use MPI-IO and its collective operations.

WWW: http://trac.mcs.anl.gov/projects/parallel-netcdf